Process for polymerizing olefins in the presence of a catalyst prepared from an organomagnesium component which does not reduce TiCl4

ABSTRACT

Solid supported catalysts which can be employed for the polymerization of α-olefins are prepared by (A) reacting in the presence of a diluent such as n-hexane a mixture of (1) the reaction product of (a) an organo magnesium compound such as dibutyl magnesium and (b) at least one of water, carbon dioxide or an organic, oxygen-containing compound such as n-propyl alcohol; and (2) a transition metal halide such as titanium tetrachloride and (B) recovering the solid precipitate such as by decanting and (C) washing the solid with a solvent such as n-hexane. The resultant solid supported catalyst contains sufficient transition metal which when activated with a suitable activating agent serves as a polymerization catalyst for α-olefins. The polymers prepared employing these catalysts have a relatively narrow molecular weight distribution and low residual amounts of transition metal and halides.

BACKGROUND OF THE INVENTION

This invention relates to a new catalyst composition useful forinitiating and promoting polymerization of α-olefins and to apolymerization process employing such a catalyst compostion.

It is well known that olefins such as ethylene, propylene, and 1-butenein the presence of metallic catalysts, particularly the reactionproducts of organometallic compounds and transition metal compounds canbe polymerized to form substantially linear polymers of relatively highmolecular weight. Typically such polymerizations are carried out atrelatively low temperatures and pressures.

Among the methods for producing such linear olefin polymers, some of themost widely utilized are those described by Professor Karl Ziegler inU.S. Pat. Nos. 3,113,115 and 3,257,332. In these methods, the catalystemployed is obtained by admixing a compound of a transition metal ofGroups 4b, 5b, 6b and 8 of Mendeleeve's Periodic Table of Elements withan organometallic compound. Generally the halides, oxyhalides andalkoxides or esters of titanium, vanadium and zirconium are the mostwidely used transition metal compounds. Common examples of theorganometallic compounds include the hydride, alkyls and haloalkyls ofaluminum, alkylaluminum halides, Grignard reagents, alkali metalaluminum hydrides, alkali metal borohydrides, alkali metal hydrides,alkaline earth metal hydrides and the like. Usually, the polymerizationis carried out in a reaction medium comprising an inert organic liquid,e.g., an aliphatic hydrocarbon and the aforementioned catalyst. One ormore olefins may be brought into contact with the reaction medium in anysuitable manner, and a molecular weight regulator, such as hydrogen, isoften added to the reaction vessel in order to control the molecularweight of the polymers. Such polymerization processes are either carriedout at slurry polymerization temperatures (i.e., wherein the resultingpolymer is not dissolved in the hydrocarbon reaction medium) or atsolution polymerization temperatures (i.e., wherein the temperature ishigh enough to solubilize the polymer in the reaction medium).

Following polymerization, it is common to remove catalyst residues fromthe polymer by repeatedly treating the polymer with alcohol or otherdeactivating agents such as an aqueous basic solution. Such catalystdeactivation and/or removal procedures are expensive both in time andmaterial consumed as well as the equipment required to carry out suchtreatment.

Moreover, most slurry polymerization processes employing theaforementioned known catalyst systems are accompanied by reactor foulingproblems. As a result of such reactor fouling, it is necessary tofrequently stop the process to clean the polymerization reactor.

In view of the foregoing problems encountered in the use of conventionalZiegler catalysts, it would be highly desirable to provide apolymerization catalyst which is sufficiently active to eliminate theneed for catalyst residue removal and which minimizes reactor foulingproblems. In slurry polymerization processes, it would be especiallydesirable to provide a high efficiency catalyst that will yield apolyolefin powder having an unsettled bulk density of 20-35 pounds percubic foot.

SUMMARY OF THE INVENTION

The present invention in one aspect is the hydrocarbon insoluble solidcatalytic reaction product of (1) the reaction product of (a) ahydrocarbyl magnesium compound or a hydrocarbyl or hydrocarbyloxyaluminum, zinc or boron mixture or complex thereof with (b) at least oneof water, carbon dioxide or an organic, oxygen-containing compound freeof halogen and nitrogen atoms and (2) a halide-containing transitionmetal compound or mixture thereof.

The components are employed in quantities such that a sufficient amountof component (1-b) is employed so as to react with the hydrocarbyl grouppresent in component (1-a) which results in a product which will notsubstantially reduce TiCl₄ at a temperature of about 25° C. A sufficientquantity of halide-containing transition metal compound is employed soas to convert substantially all of the organic groups attached to amagnesium atom in component (1) to a halide group. The halogen:Mg ratiois usually from about 500:1 to about 2:1, preferably from about 100:1 toabout 3:1 and most preferably from about 50:1 to about 4:1. The Mg:Tiratio is usually from about 0.01:1 to about 1.5:1, preferably from about0.1:1 to about 1:1. The water, carbon dioxide or organic,oxygen-containing compound is preferably employed in sufficientquantities to lower the hydrocarbyl content of component (1-a) to avalue as close to zero as is practically possible within a reasonableperiod of time.

A suitable test for determining whether or not the quantity of component(1-b) is sufficient to lower the amount of hydrocarbyl groups present incomponent (1-a) to produce a product which will not substantially reduceTiCl₄ at 25° C. is to take an aliquot of the reaction product ofcomponents (1-a) and (1-b) and remove or add organic diluent therebyadjusting the magnesium component to about 0.2 molar. Then add 5milliliters of a TiCl₄ solution which is at least 1 molar in ahydrocarbon to 50 milliliters of the about 0.2 molar sample. If theresultant slurry turns brown or blackish brown, considerable reductionof TiCl₄ has occurred, which is undesirable. A slight tan color isindicative of only slight reduction (i.e. not substantial) and isacceptable. Most desirable is a white or yellowish white color whichindicates essentially no reduction of TiCl₄.

The present invention in another aspect is the solid catalyst obtainedfrom contacting the above solid supported catalyst with an activatingagent.

The present invention also concerns a process for preparing ahydrocarbon insoluble solid catalyst which process comprises

(A) reacting in the presence of an inert diluent

(1) the reaction product of

(a) a magnesium component or mixture of such components represented bythe formula MgR₂.xMeR'_(x') wherein each R is independently ahydrocarbyl group having from 1 to about 20, preferably from 1 to about10 carbon atoms, each R' is independently a hydrocarbyl or ahydrocarbyloxy group having from 1 to about 20, preferably from 1 toabout 10 carbon atoms, Me is aluminum, zinc or boron, x has a value offrom zero to about 10 and x' has a value equal to the valence of Me;with

(b) a sufficient amount of at least one of water, carbon dioxide or anorganic, oxygen-containing compound free of halogen and nitrogen atomsso as to react with the hydrocarbyl groups present in component (1-a) toproduce a product which will not substantially reduce TiCl₄ at atemperature of about 25° C.; with

(2) a halide-containing transition metal compound or mixture thereofrepresented by the formula TmY_(n) X_(z-n) wherein Tm is a metalselected from groups IV-B, V-B and VI-B of the Periodic Table ofElements, Y is oxygen or OR", each X is a halogen, each R" isindependently a hydrocarbyl group having from 1 to about 20 carbonatoms, z has a value equal to the valence of said transition metal, nhas a value of from zero to 6 with the value of z-n being from at least1 up to a value equal to the valence of the transition metal; saidhalide-containing transition metal being present in a quantity so as toconvert substantially all of the substituent groups attached to amagnesium atom in component (1) to a halide group;

(B) recovering the resultant hydrocarbon insoluble reaction producttherefrom;

(C) reacting said hydrocarbon insoluble reaction product with anactivating agent represented by the formulas AlR³ _(3-m) X_(m), ZnR³ ₂,ZnR³ X, MgR³ X or MgR³ ₂ including mixtures thereof wherein each R³ isindependently a hydrocarbyl group, X is a halogen, preferably chlorineor bromine, or a hydrocarbyloxy group, m has a value from zero to 2,preferably zero or 1 and most preferably zero in a quantity so as toprovide an Al, Zn and/or Mg:Tm ratio of from about 1:1 to about 5000:1,preferably from 5:1 to about 1000:1 and most preferably from 10:1 toabout 400:1.

Another aspect of the invention is a process for polymerizing α-olefinsor mixtures thereof which comprises conducting the polymerization in thepresence of the aforementioned catalysts.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The organo magnesium compounds which are suitably employed in thepresent invention include those represented by the formula R₂Mg.xMeR'_(x') wherein each R is independently a hydrocarbyl group, eachR' is independently a hydrocarbyl or hydrocarbyloxy group, Me isaluminum, zinc or boron and x' has a value equal to the valence of themetal Me.

The term hydrocarbyl as employed herein refers to a monovalent and insome instances a divalent hydrocarbon radical such as alkyl cycloalkyl,aryl, aralkyl, alkenyl and similar hydrocarbon radicals having from 1 toabout 20 carbon atoms with alkyl having from 1 to 10 carbon atoms beingpreferred.

The term hydrocarbyloxy as employed herein refers to monovalentoxyhydrocarbon radicals such as alkoxy, cycloalkoxy, aryloxy, aralkoxy,alkenoxy and similar oxyhydrocarbon atoms having from 1 to about 20carbon atoms with alkoxy groups having from 1 to 10 carbon atoms beingthe preferred hydrocarbyloxy radicals.

The quantity of MeR'_(x') i.e. the value of x, is preferably from theminimum amount which is sufficient to render the magnesium compoundsoluble in the inert solvent or diluent which is usually a hydrocarbonor mixture of hydrocarbons up to a value of about 10. The value of xtherefore is from zero to about 10, usually from zero to about 2,preferably from about 0.2 to about 1. Most preferably, the value of x issuch that the reaction product (1) is hydrocarbon soluble. When carbondioxide is employed alone as component (1-a), x must have a valuegreater than zero, preferably from about 0.1 to about 5.0 and mostpreferably from about 0.5 to about 2.0.

Particularly suitable organomagnesium compounds include, for example,di-(n-butyl) magnesium, n-butyl-secbutylmagnesium, diisopropylmagnesium,di-n-hexylmagnesium, isopropyl-n-butyl magnesium, ethyl-n-hexylmagnesium, ethyl-n-butylmagnesium, di-n-butylmagnesium.1/2triisobutylaluminum, di-(n-butyl)magnesium.1/6 triethylaluminum,dibutylmagnesium.2 triisobutylaluminum, butyl-octylmagnesium,dihexylmagnesium.1/2 triisobutylaluminum, butylethylmagnesium.1/2triisobutylaluminum, butyloctylmagnesium.1/2 triisobutylaluminum,mixtures thereof and the like.

Suitable organic, oxygen-containing compounds free of halogen andnitrogen atoms which can be employed herein as component (1-b) include,for example, hydroxyl-containing compounds such as alcohols, glycols,polyoxyalkyleneglycols, aldehydes, ketones, carboylic acids, acetals,ketals, esters of carboxylic acids, orthoesters, anhydrides ofcarboxylic acids, carbonates, mixtures thereof and the like. It ispreferred that these compounds be liquids at the temperature at whichthe catalyst is prepared and also be miscible with the inert diluent inwhich the catalyst is prepared.

Suitable hydroxyl-containing compounds include those represented byformulas

    ROH, R--O--R'--.sub.n OH and Z--O--R'--.sub.n O--R"].sub.n'

wherein each R is hydrogen or a hydrocarbyl group having from 1 to about20 carbon atoms, each R' is independently a divalent hydrocarbyl grouphaving from 1 to about 20 carbon atoms, each R" is independentlyhydrogen or a hydrocarbyl group having from 1 to about 20 carbon atoms,at least one of which is hydrogen, Z is a multivalent organic radicalcontaining from 2 to about 20 carbon atoms, n has a value from zero toabout 40 and n' has a value of from 3 to about 8. Practically, thevalues of n and n' are such that the hydroxyl-containing compounds areliquids at the catalyst preparation temperature.

Particularly suitable hydroxyl-containing compounds include alcoholssuch as, for example methyl alcohol, ethyl alcohol, n-propyl alcohol,isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butylalcohol phenol 2,6-diisopropylphenol, glycols such as, for example,ethylene glycol, 1,2-propylene glycol, 1,2-butylene glycol,1,3-propylene glycol, 1,4-butanediol, 1,6-hexane diol, other hydroxylcontaining compounds such as, for example, glycerine, trimethylalpropane and pentaerythritol, as well as adducts of ethylene oxide,1,2-propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, styreneoxide or mixtures of such oxides with the previously mentionedhydroxyl-containing compounds as well as the alkyl and aryl cappedhydroxyl-containing compounds so long as there remains at least 1hydroxyl group per molecule.

Suitable aldehydes which can be employed herein include those aldehydesrepresented by the formula ##STR1## wherein R is hydrogen or ahydrocarbyl group having from 1 to about 20 carbon atoms, preferably analiphatic hydrocarbyl group having from 1 to about 10 carbon atoms.Particularly suitable aldehydes include, for example, formaldehyde,acetaldehyde, propionaldehyde, butryaldehyde, benzaldehyde, mixturesthereof and the like.

Suitable ketones which can be employed herein include, for example,those represented by the formula ##STR2## wherein each R isindependently a hydrocarbyl group having from 1 to about 20 carbonatoms, preferably from 1 to about 10 carbon atoms. Particularly suitableketones include, for example, acetone, methyl ethyl ketone,2,6-dimethyl-4-heptanone, mixtures thereof and the like.

The hydroxyl-containing materials, particularly the alcohols, and thealdehydes and ketones, can contain up to about 50% water by weight andpreferably up to about 1 percent water by weight.

Suitable carboxylic acids which can be employed herein include thoserepresented by the formulas ##STR3## wherein each R is a hydrocarbylgroup having from 1 to about 20 carbon atoms, particularly from about 1to about 10 carbon atoms. Particularly suitable carboxylic acidsinclude, for example, formic acid, acetic acid, propionic acid, oxalicacid, benzoic acid, 2-ethylhexanoic acid, acrylic acid, mixtures thereofand the like.

Suitable acetals which can be employed herein include, for example,those represented by the formula ##STR4## wherein each R isindependently a hydrocarbyl group having from 1 to about 20 carbonatoms, preferably from 1 to about 10 carbon atoms. Particularly suitableacetals which can be employed includes, for example, acetal,1,1-diethoxypropane, mixtures thereof and the like.

Suitable ketals which can be employed herein include, for example, thoserepresented by the formula ##STR5## wherein each R is independently ahydrocarbyl group having from 1 to about 20 carbon atoms, preferablyfrom 1 to about 10 carbon atoms. Particularly suitable ketals include,for example, 2,2-dimethoxypropane, 2,2-dimethoxyhexane,2,2-diethoxypropane, mixtures thereof and the like.

Suitable exsters of carboxylic acids which can be employed hereininclude, for example, those represented by the formulas ##STR6## whereineach R is independently a hydrocarbyl group having from 1 to about 20carbon atoms, preferably from 1 to about 10 carbon atoms. Particularlysuitable esters include, for example, ethyl acetate, ethyl formate,ethyl benzoate, methyl acetate, methyl formate, mixtures thereof and thelike.

Suitable orthoesters which can be employed herein include, for example,those represented by the formula ##STR7## wherein each R isindependently a hydrocarbyl group having from 1 to about 20 carbonatoms, preferably from 1 to about 10 carbon atoms. Particularly suitableorthoesters include, for example, triethylorthoformate,triethylorthoacetate mixtures thereof and the like.

Suitable carbonates which can be employed herein include, for example,those represented by the formulas ##STR8## wherein each R isindependently a hydrocarbyl group having from 1 to about 20 carbonatoms, preferably from 1 to about 10 carbon atoms. Particularly suitablecarbonates include, for example, diethylcarbonate, ethylene carbonate,dipropylcarbonate, propylene carbonate, styrene carbonate, mixturesthereof and the like.

Suitable carboxylic acid anhydrides include, for example, thoserepresented by the formulas ##STR9## wherein each R is independently ahydrocarbyl group having from 1 to about 20 carbon atoms, preferablyfrom 1 to about 10 carbon atoms. Particularly suitable anhydridesinclude, for example, acetic anhydride, propionic anhydride mixturesthereof and the like.

Suitable halide-containing transition metal compounds which can beemployed include those compounds represented by the formula TmY_(n)X_(z-n) wherein Tm is a transition metal selected from groups IV-B, V-Band VI-B of the Periodic Table of the Elements, Y is oxygen or OR", eachR" is independently a hydrocarbyl group as previously defined, X is ahalogen, preferably chlorine or bromine, z has a value corresponding tothe valence of the transition metal, Tm, n has a value of from zero to 6with the value of z-n being from at least 1 up to a value equal to thevalence state of the transition metal, Tm.

Particularly suitable are the hydrocarbon soluble transition metalcompounds such as, for example, titanium tetrachloride, titaniumtetrabromide, dibutoxy titanium dichloride, monoethoxytitaniumtrichloride, vanadium oxytrichloride, vanadium tetrachloride, chromiumtrichloride, mixtures thereof and the like.

Suitable organic inert diluents in which the catalysts can be preparedand in which the α-olefin polymerization can be conducted include, forexample, liquified ethane, propane, isobutane, n-butane, n-hexane, thevarious isomeric hexanes, isooctane, paraffinic mixtures of alkaneshaving from 8 to 12 carbon atoms, cyclohexane, methylcyclopentane,dimethylcyclohexane, dodecane, industrial solvents composed of saturatedor aromatic hydrocarbons such as kerosene, naphthas, etc., especiallywhen freed of any olefin compounds and other impurities, especiallythose having boiling points in the range from about -50° to about 200°C. Also included as suitable inert diluents are benzene, toluene,ethylbenzene, cumene, decalin and the like. Most suitable are thehydrocarbons having from 4 to about 10 carbon atoms.

The catalysts of the present invention are advantageously prepared underan inert atmosphere such as nigrogen, argon or other inert gas attemperatures in the range of from about 50° C. to about 200° C.,preferably for convenience from about 0° C. to about 100° C. The time ofmixing the various components is not critical; however, times of fromabout 5 minutes to about 2 hours are deemed to be most desirable. Rapidmixing of the catalyst components or poor agitation produces a catalystwhich is relatively non-uniform with respect to particle sizedistribution amd produces polymers having an undesirably broad particlesize distribution.

The magnesium compound, the optional aluminum compound, and the water,carbon dioxide or organic oxygen-containing compound may be mixed in anyorder of addition. A gelatinous precipitate forms when theoxygen-containing compound and magnesium compound are mixed and lumpswill form if the reactants are mixed either with poor agitation, toorapidly or in too concentrated a mixture. These lumps result in a finalcatalyst which contains lumps which in turn produces a polymer underslurry polymerization conditions having an undesirably broad particlesize distribution with a significant percentage of particles unable topass through a 40 mesh screen. Addition of an aluminum compound resultsin a hydrocarbon solution of the magnesium compund and oxygen-containingcompound mixture and eliminates these previously mentioned undesirableeffects. It is preferable to add the oxygen-containing compound to asolution of the magnesium compound and the aluminum compound so as toobtain a desirably uniform polymer particle size distribution.

When the catalysts of this invention are used in solution polymerizationconditions the above mentioned catalyst particle size distribution isnot as important; however, if an aluminum compound is added as asolubilizing agent the catalyst preparation is simplified when usingclosed metal vessels for the catalyst preparation, such as would be usedin the commercial production of polymers and copolymers of ethylene.

Suitable activating agents or catalysts with which the supportedcatalysts of the present invention can be reacted, contacted or employedin the polymerization of α-olefins include those aluminum, zinc ormagnesium compounds represented by the formulas AlR³ _(3-m) X_(m), ZnR³₂, ZnR³ X, MgR³ X or MgR³ ₂ including mixtures thereof wherein each R³is independently a hydrocarbyl group as hereinbefore defined, X is ahalogen, preferably chlorine or bromine, or a hydrocarbyloxy group ashereinbefore defined, m has a value of from zero to 2, preferably zeroor 1 and most preferably zero.

Particularly suitable activating agents or cocatalysts include, forexample, diethylaluminum chloride, diethylaluminum bromide,triethylaluminum, triisobutylaluminum, diethylaluminum ethoxide,dibutylmagnesium, mixtures thereof and the like.

The activators are employed in quantities such that the Al, Mg and/orZn:Tm atomic ratio is from about 1:1 to about 5000:1, preferably fromabout 5:1 to about 1000:1 and most preferably from about 10:1 to about400:1.

Olefins which are suitably homopolymerized or copolymerized in thepractice of this invention are generally the aliphatic α-monoolefins orα-diolefins having from 2 to 18 carbon atoms. Illstratively, suchα-olefins can include ethylene, propylene, butene-1, pentene-1,3-methylbutene-1, 4-methylpentene-1, hexene-1, octene-1, dodecene-1,octadecene-1 1,7-octadiene and the like. It is understood that α-olefinsmay be copolymerized with other α-olefins and/or with small amountsi.e., up to about 25 weight percent based on the polymer of otherethylenically unsaturated monomers such as styrene, α-methylstyrene andsimilar ethylenically unsaturated monomers which do not destroyconventional Ziegler catalysts. More benefits are realized in thepolymerization of aliphatic α-monoolefins, particularly ethylene andmixtures of ethylene and up to 50, especially from about 0.1 to about 40weight percent of propylene, butene-1, hexene-1, octene-1,4-methylpentene-1, 1,7-octadiene or similar α-olefin or α-diolefin basedon total monomer.

α-olefins may be polymerized by employing mixtures of the hereindescribed catalyst support with the herein described reducingcocatalysts. The polymerization can be conducted by either (1) reactingsaid support and said cocatalyst prior to addition to the polymerizationreactor, (2) adding to the reactor a mixture of the two components or(3) adding the two components separately to the polymerization reactoror combinations thereof.

In the polymerization process employing the aforementioned catalysts,polymerization is effected by adding a catalytic amount of the abovecatalyst composition to a polymerization zone containing α-olefinmonomer, or vice versa. The polymerization zone is maintained attemperatures in the range from about 0° to about 300° C., preferablyfrom about 40° C. to about 90° C., for a residence time of about 30minutes to several hours, preferably 1 hour to 4 hours. It is desirableto carry out the polymerization in the absence of moisture and oxygenand a catalytic amount of the catalytic reaction product is generallywithin the range from about 0.0001 to about 0.01 milligram-atomstransition metal per liter of diluent. It is understood, however, thatthe most advantageous catalyst concentration will depend uponpolymerization conditions such as temperature, residence time, pressure,diluent and presence of catalyst poisons and that the foregoing range isgiven to obtain maximum catalyst yields. Generally in the polymerizationprocess, a carrier which may be an inert organic diluent or excessmonomer is generally employed. In order to realize the full benefit ofthe high efficiency catalyst of the present invention care must be takento avoid oversaturation of the diluent with polymer. If such saturationoccurs before the catalyst becomes depleted, the full efficiency of thecatalyst is not realized. For best results, it is preferred that theamount of polymer in the carrier not exceed about 50 weight percentbased on the total weight of the reaction mixture.

It is understood that suitable inert diluents employed in thepolymerization recipe are as defined as hereinbefore for use inpreparation of the catalyst.

The polymerization pressures preferably employed are relatively low,e.g., from about 50 to about 500 psig. However, polymerization withinthe scope of the present invention can occur at pressures fromatomospheric up to pressures determined by the capabilities of thepolymerization equipment. During polymerization it is desirable to mixthe polymerization recipe to obtain better temperature control and tomaintain uniform polymerization mixtures throughout the polymerizationzone.

In order to optimize catalyst yields in the polymerization of ethyleneat solution polymerization conditions, it is preferred to maintain anethylene concentration in the solvent in the range from about 0.1 toabout 10 weight percent. To achieve this concentration when an excess ofethylene is fed into the system, a portion of the ethylene can bevented. Hydrogen is often employed in the practice of this invention tolower molecular weight of the resultant polymer. For the purpose of thisinvention, it is beneficial to employ hydrogen in concentrations rangingfrom about 0 to about 80 volume percent in the gas phase in thepolymerization vessel. The larger amounts of hydrogen within this rangeare found to produce generally lower molecular weight polymers. It isunderstood that hydrogen can be added with a monomer stream to thepolymerization vessel or separately added to the vessel before, duringor after addition of the monomer to the polymerization vessel, butduring or before the addition of the catalyst. Using the general methodsdescribed herein, the polymerization reactor can be operated liquid fullor with a gas phase and either at solution or slurry polymerizationconditions.

The monomer or mixture of monomers is contacted with the catalyticreaction produce in any conventional manner, preferably by bringing thecatalyst composition and monomer together with intimate agitationprovided by suitable stirring or other means. Agitation can be continuedduring polymerization. In the case of more rapid reactions with moreactive catalysts, means can be provided for refluxing monomer andsolvent, if any of the latter is present and thus remove the heat ofreaction. In any event, adequate means should be provided fordissipating the exothermic heat of polymerization, e.g., by coolingreactor walls, etc. If desired, the monomer can be brought in the vaporphase into contact with the catalytic reaction product, in the presenceor absence of liquid material. The polymerization can be effected in thebatch manner, or in a continuous manner, such as, for example, bypassing the reaction mixture through an elongated reaction tube which iscontacted externally with suitable cooling medium to maintain thedesired reaction temperature, or by passing the reaction mixture throughan equilibrium overflow reactor or a series of the same.

The polymer is readily recovered from the polymerization mixture bydriving off unreacted monomer and solvent if any is employed. No furtherremoval of impurities is required. Thus, a significant advantage of thepresent invention is the elimination of the catalyst residue removalsteps and minimize contamination of the polymer with corrosive chlorideresidues. In some instances, however, it may be desirable to add a smallamount of a catalyst deactivating reagent. The resultant polymer isfound to contain insignificant amounts of catalyst residue.

The following examples are given to illustrate the invention, and shouldnot be construed as limiting its scope. All parts and percentages are byweight unless otherwise indicated.

In the following examples, the melt index values I₂, were determined byASTM D 1238, condition E. The apparent bulk density was determined as anunsettled bulk density according to the procedure of ASTM 1895 employinga paint volumeter from the Sargent-Welch Scientific Company (catalog no.S-64985) as the cylinder instead of the one specified by the ASTMprocedure.

GENERAL PROCEDURE

In each of the following examples, the catalyst components were blendedwhile in a gloved box filled with nitrogen unless otherwise indicated.In the examples, the dibutylmagnesium was a commercial material obtainedfrom the Lithium Corporation of America and the dihexylmagnesium was acommercial material obtained from the Ethyl Corporation. All ratios aremolar ratios unless otherwise indicated.

EXAMPLE 1 (a) Catalyst Preparation:

Seventy-five milliliters (1 mole) of n-propylalcohol dissolved in hexane(200 ml.) was slowly added to a stirred solution of 1053 ml. (0.5 mole)of 0.475 molar dibutylmagnesium in a heptane-cyclohexane mixture.Titanium tetrachloride (110 ml., 1 mole) was added dropwise to theresultant slurry with continuous stirring. After 1/2 hour thehydrocarbon insoluble products were allowed to settle and thesupernatant solution was removed by decantation. The solids werereslurried with fresh hexane. The decantation was repeated four moretimes to remove hexane soluble reaction products.

The catalyst components were mixed to give an alcohol to magnesium molarratio of 2:1 and a magnesium to titanium atomic ratio of 0.5:1. Afterthe decantations, a hexane slurry of the solid catalyst was found byanalysis to have a magnesium to titanium atomic ratio of 2.6:1 and achloride to magnesium atomic ratio of 3.0:1.

(b) Polymerization of Ethylene:

An aliquot of catalyst slurry, prepared in (a) above, containing 0.005millimole of titanium was added to a 1.8 liter stirred stainless steelreactor containing 1.0 liter of dry oxygen free hexane, and 1.6 mol of0.616 molar ATB (triisobutylaluminum) in hexane. The atomic ratio ofAl:Ti was 200:1. The reactor nitrogen atmosphere was replaced withhydrogen by purging, the reactor contents were heated to 85° C., and thereactor pressure was adjusted to 60 psig (pounds per square inch gauge)with hydrogen. Ethylene was then added to maintain a reactor pressure of170 psig. After two hours at 85° C., the reactor contents were filteredand the polyethylene dried in a vacuum overnight at about 60° C. toyield 288 g. polyethylene with a melt index of 0.47 and a bulk densityof 19.3 pounds per cubic foot.

Catalyst efficiency was 1,200,000 grams polyethylene per gram titanium.Using the Cl, Mg, and Ti analysis of the catalyst slurry, thecomposition was calculated to be 2.6 MgCl₂.TiCl₂.6 (OnPr)₁.4. Thiscalculated composition then provides a calculated catalyst efficiency of122,000 g. PE/g. catalyst. This demonstrates that the catalystefficiency based on total solid catalyst is very high.

EXAMPLE 2 (a) Catalyst Preparation

ATB (0.616 molar, 203 ml., 0.13 mole), dihexylmagnesium (0.593 molar inhexane, 420 ml., 0.25 mole), hexane (900 ml.), and n-propylalcohol (76ml.) were mixed to give a solution. To this solution was added dropwisea solution of 55 ml. (0.5 mole) titanium tetrachloride dissolved in 200ml. of hexane. A uniform white solid formed and was decanted as inExample (1-a) to remove the hydrocarbon soluble products. The atomicratio of magnesium to titanium in the catalyst preperation was 0.50 andafter decanting was 3.6.

(b) Polymerization of Ethylene

The catalyst slurry from example (2-a) was used in the method describedin example (1-b). Polyethylene (157 g.) having a melt index of 0.20 anda bulk density of 16.5 pounds per cubic foot was obtained. The catalystefficiency was 656,000 grams of polyethylene per gram of titanium.

Analysis of the polyethylene powder obtained from (2-b) and (1-b) showsthat the powder of (2-b) had 100% of its particles smaller than 400microns while the powder from (1-b) had 31% of its particles larger than400 microns. These large particles or "lumps" found in the polyethylenefrom the non-solubilized catalyst are undesirable in a continuousprocess production plant; therefore, it is preferred that theorganomagnesium compound-alcohol reaction product be hydrocarbon solubleby mixing or complexing the organomagnesium compound with an aluminum,zinc or boron organometallic compound.

COMPARATIVE EXPERIMENT A (a) Catalyst Preparation

The procedure described in example 1 of British Pat. No. 1,275,641(Solvay Et Cie) was repeated using magnesium ethoxide from the AlfaDivision, Ventron Corporation.

(b) Polymerization of Ethylene

Triisobutylaluminum (4.0 millimoles, 6.5 ml. of 0.616 M in hexane) andan aliquot of catalyst containing 0.02 millimole of titanium were addedto a stirred 1.8 liter reactor containing 1.0 liter of dry, oxygen-freehexane. The nitrogen atmosphere in the reactor was replaced withhydrogen, the reactor contents heated to 85° C., and the reactorpressure adjusted to 70 psig with hydrogen. Ethylene was then added tomaintain a reactor pressure of 170 psig. After two hours the reactorcontents were filtered and the polyethylene dried in a vacuum overnightat about 60° C. The polyethylene obtained weighed 157 grams, had a meltindex of 0.85 and had a bulk density of 16.7 pounds per cubic foot. Thecatalyst efficiency was 164,000 grams of polyethylene per gram oftitanium.

EXAMPLE 3 (a) Catalyst Preparation

A series of catalysts were prepared in which the Mg:Ti ratio of thecomponents was varied. A solution of n-propylalcohol in 100 ml. hexanewas slowly added to a hydrocarbon solution of dibutylmagnesium andtriisobutylaluminum. After cooling to about 25° C., a 1.0 molar titaniumtetrachloride solution in hexane was added dropwise. The resultant whiteslurry was stirred for one hour, the solids allowed to settle and thesupernatant liquid removed by decantation. The solids were reslurriedwith fresh hexane and the decantation procedure repeated 5 additionaltimes to remove most of the hexane soluble titanium species. Table Ishows the exact quantities of the catalyst components.

                                      TABLE I                                     __________________________________________________________________________         0.583 M                                                                             0.616 M tri-                                                            dibutyl-                                                                            isobutyl-                                                                           n-propyl-                                                                           1.0 M                                                  Catalyst                                                                           magnesium                                                                           aluminum                                                                            alcohol,                                                                            TiCl.sub.4                                                                         Mg:Ti in Catalyst                                                                      Cl:Mg in Catalyst                        No.  ml./mole                                                                            ml./mole                                                                            ml./mole                                                                            ml./mole                                                                           Preparation                                                                            Preparation                              __________________________________________________________________________    A    214/0.125                                                                           102/0.0628                                                                          32.9/0.438                                                                          833/0.833                                                                          0.15:1   27:1                                     B    214/0.125                                                                           102/0.0628                                                                          32.9/0.438                                                                          500/0.5                                                                            0.25:1   16:1                                     C    214/0.125                                                                           102/0.0628                                                                          32.9/0.438                                                                          250/0.25                                                                           0.50:1    8:1                                     D    214/0.125                                                                           102/0.0628                                                                          32.9/0.438                                                                          125/0.125                                                                          1.00      4:1                                     __________________________________________________________________________

(b) Polymerization of Ethylene

The polymerization procedure of Example (1-b) was repeated using 90 psighydrogen instead of 60 psig and the catalyst and cocatalyst quantitiesand the polymerization results are shown in Table II.

                  TABLE II                                                        ______________________________________                                                                           Cata-                                                   Cocatalyst            lyst       Bulk                            Cat- Cata-   .616 M                Effi-      Den-                            a-   lyst, m triisobutyl     Poly- ciency                                                                              Melt sity                            lyst moles   aluminum        ethy- g PE/ In-  lbs/                            No.  Ti      ml/mole   Al:Ti lene g.                                                                             g Ti  dex  ft.sup.3                        ______________________________________                                        A    .0048    1.6/0.986                                                                              205:1  95   413,000                                                                             6.9  19.9                            B    .0063   2.0/1.23  195:1 250   828,000                                                                             8.4  20.3                            C    .0053   1.7/1.05  198:1 101   398,000                                                                             3.2  14.5                            D    .0176   5.6/3.45  196:1 173   205,000                                                                             5.1  15.8                            ______________________________________                                    

EXAMPLE 4 (a) Catalyst Preparation

A series of catalyst were prepared in which the amount of alcohol usedin the catalyst preparation was varied. A solution of n-propylalcohol in50 ml. hexane was slowly added to a hydrocarbon solution ofdibutylmagnesium and triisobutylaluminum. After cooling to about 25° C.,a 1.0 molar titanium tetrachloride solution in hexane was addeddropwise. The resultant slurry was stirred for one hour, the solidsallowed to settle and the supernatant liquid was removed by decantation.The solids were reslurried with fresh hexane and the decantationprocedure was repeated 5 additional times to remove most of the hexanesoluble titanium species. Table III shows the exact quantities of thecatalyst components.

                                      TABLE III                                   __________________________________________________________________________                               Molar ratio of alcohol                                                                    Color of                                    0.583 M                                                                             0.616 M tri-    per alkyl group present                                                                   solid                                       dibutyl-                                                                            isobutyl-                                                                           n-propyl-                                                                          1.0 M                                                                              in the alkyl magnesium                                                                    precipitate                            Catalyst                                                                           magnesium                                                                           aluminum                                                                            alcohol,                                                                           TiCl.sub.4                                                                         and alkyl aluminum                                                                        After Addition                         No.  ml./mole                                                                            ml./mole                                                                            ml./mole                                                                           ml./mole                                                                           mixture     of TiCl.sub.4                          __________________________________________________________________________     A   107/0.06                                                                            50.8/0.03                                                                           13.2/0.18                                                                          250/0.25                                                                           0.86        tan                                    B    107/0.06                                                                            50.8/0.03                                                                           14.8/0.2                                                                           250/0.25                                                                           0.95        tan                                    C.sup.1                                                                            214/0.12                                                                            102/0.06                                                                            32.9/0.44                                                                          500/0.05                                                                           1.05        white                                  D    107/0.06                                                                            50.8/0.04                                                                           19.8/0.26                                                                          250/0.25                                                                           1.08        white                                  E    107/0.06                                                                            50.8/0.04                                                                           23.1/0.31                                                                          250/0.25                                                                           1.29        white                                  F.sup.2                                                                            211.sup.3 /0.13                                                                     102/0.06                                                                             9.4/0.13                                                                          500/0.5                                                                            0.3         brown                                  G    214/0.12                                                                            102/0.06                                                                            37.8.sup.4 /.50                                                                    500/.50                                                                            1.19        white                                  __________________________________________________________________________     .sup.1 Same as Catalyst No. B of Example 3, alcohol diluted with 200 m.       hexane.                                                                       .sup.2 Comparative Experiment. The reaction product of the alcohol and        organomagnesium compoundorganoaluminum compound mixture substantially         reduced TiCl.sub.4 as evidenced by the brown                                  .sup.3 The dibutylmagnesium was 0.593 M instead of 0.583 M.                   .sup.4 The npropylalcohol contained 5000 parts per million of water by        weight.                                                                  

(b) Polymerization of Ethylene

The polymerization procedure of Example (3b) was repeated and theresults listed in Table IV.

                  TABLE IV                                                        ______________________________________                                                                           Cata-                                                   Cocatalyst            lyst       Bulk                            Cat- Cata-   .616 M                Effi-      Den-                            a-   lyst, m tirisobutyl     Poly- ciency                                                                              Melt sity                            lyst moles   aluminum        ethy- g /PE In-  lbs/                            No.  Ti      ml./mole  Al:Ti lene g.                                                                             g Ti  dex  ft.sup.3                        ______________________________________                                        A    .0054   1.7/1.05  194:1  94   363,000                                                                             2.1  16.9                            B    .0054   1.8/1.11  206:1 121   468,000                                                                             2.9  14.9                            C*   .0063   2.0/1.23  195:1 250   828,000                                                                             8.4  20.3                            D    .0049   1.6/0.99  202:1 197   839,000                                                                             2.5  15.4                            E    .0052   1.6/0.99  190:1  55   221,000                                                                             1.7  12.8                            F**  .0060   0.8/0.49   82:1  0    0     --   --                              F**  .050    8.1/4.99  100:1  45    18,000                                                                             0.3  8.3                             G    .0056   1.8/1.11  198:1 155   578,000                                                                             2.9  23.3                            ______________________________________                                         *same as catalyst No. B of Example 3.                                         **Comparative Experiment.                                                

COMPARATIVE EXPERIMENT B (a) Catalyst Preparation

A 1.0 molar TiCl₄ solution (110 ml.) was added dropwise at roomtemperature to a stirred slurry of 10.8 g. of finely powdered magnesiummethoxide (obtained from Alfa Division of the Ventron Corporation) in390 ml. hexane. The mixture was stirred for one hour and the solidsallowed to settle. The supernatant solution was removed by decantation,the solids were reslurried with fresh hexane and the decantationprocedure was repeated five additional times. Analysis of the resultanthexane slurry gave an Mg:Ti ratio of 560:1.

(b) Polymerization of Ethylene

The polymerization procedure of Example (3b) was repeated using analiquot of the catalyst from (a) above containing 0.09 millimoles oftitanium and enough triisobutylaluminum to give an Al:Ti ratio of 200:1.After two hours, no polyethylene was obtained.

EXAMPLE 5 (a) Catalyst Preparation

A solution (444 pounds) of dibutylmagnesium in heptane containing 2.11%magnesium and 18.2% triisobutylaluminum in hexane were mixed in stirred,jacketed 320 gallon reactor. Cooling was added to the vessel jacket andn-propylalcohol (97 pounds) was added at a rate such that thetemperature of the reactor contents did not rise above 30° C. Thereactor contents were then maintained at 15° to 20° C. and a solution of183 pounds titanium tetrachloride in 248 pounds of hexane was added at arate of about 3 pounds per minute. The resultant white slurry was thentransferred to a 900 gallon stirred reactor and diluted with 3,000pounds of hexane. The resultant slurry was allowed to settle and thesupernatant liquid removed by decantation. The solids were reslurriedwith fresh hexane and the decantation procedure repeated 5 more times.The resultant hexane slurry contained 8.2 millimoles of titanium permilliliter and the supernatant liquid, after all the solids had settled,contained less than 1 millimole of titanium per milliliter. The Mg:Tiratio of the solid was 4:1.

(b) Polymerization of Ethylene

The catalyst prepared in Example (5a) was diluted to 0.15 millimolar intitanium. This diluted catalyst was then added at a rate of 1000 to 1600pounds per hour to a two-thirds full, 20,000 gallon, jacketed reactor.Hydrogen was added to maintain 64% hydrogen by volume in the gas phaseof the reactor. Simultaneously, 10,000 pounds of ethylene and 17,500pounds of hexane per hour were added to the reactor while the reactortemperature and pressure were controlled at 85° C. and 170 psigrespectively. The reactor contents were continuously removed, thepolyethylene and hexane separated and the dried polyethylene collected.The polyethylene had a melt index of 8. The catalyst efficiency wasabout 600,000 pounds of polyethylene per pound of titanium.

EXAMPLE 6 (a) Catalyst Preparation

Catalysts were prepared in which the oxygen-containing organic compoundwas different than an alcohol. Thus, an oxygen-containing organiccompound was mixed with 100 ml. of hexane and slowly added to a stirredsolution of dibutylmagnesium in heptane. At about 25° C., a 1.0 molarsolution of titanium tetrachloride in hexane was added dropwise. Theresultant white or yellow slurry (indicating that it did notsubstantially reduce TiCl₄) was stirred for one hour, the solids allowedto settle, and the supernatant liquid removed by decantation. The solidswere reslurried with fresh hexane and the decantation procedure repeated5 more times to remove most of the hexane soluble titanium species.Table V shows the exact quantities of the catalyst components.

                  TABLE V                                                         ______________________________________                                                          oxygen-                                                     Cat- Oxygen-      containing                                                  a-   containing   organic   0.593 M                                           lyst organic      compound  MgR.sub.2,                                                                            2.0 M TiCl.sub.4                          No.  compound     ml./mole  ml./mole                                                                              ml./mole                                  ______________________________________                                        A    Methyl Acetate                                                                              7.9/100  84.3/0.05                                                                             200/0.4                                   B    Acetic Anhydride                                                                            7.4/100  84.3/0.05                                                                             200/0.4                                   C    2,2-Dimeth-  12.3/100  84.3/0.05                                                                             200/0.4                                        oxypropane                                                               D    Acetic Acid   5.7/100  84.3/0.05                                                                             200/0.4                                   E    Diethylcarbonate                                                                           12.0/100  84.3/0.05                                                                             100/0.2                                   F    Acetone      12.9/175  84.3*/0.05                                                                            100/0.2                                   ______________________________________                                         *40.6 ml. (0.03 mole) of a 0.616 M ATB solution in hexane was mixed with      the MgR.sub.2.                                                           

(b) Polymerization of Ethylene

The polymerization procedure of Example (1-b) was repeated using 50 psighydrogen and the catalyst and cocatalyst quantities are shown in TableVI. The polymerization results are also listed in Table VI.

                  TABLE VI                                                        ______________________________________                                                                           Cata-                                                   Cocatalyst            lyst       Bulk                            Cat- Cata-   0.616 M               Effi-      Den-                            a-   lyst, m triisobutyl     Poly- ciency                                                                              Melt sity                            lyst moles   aluminum        ethy- g PE/ In-  lbs/                            No.  Ti      ml./mole  Al:Ti lene g.                                                                             g Ti  dex  ft.sup.3                        ______________________________________                                        A    .035    5.7/3.51  100:1 225   134,000                                                                             1.9  20.7                            B    .025    4.1/2.53  100:1  14    12,000                                                                             0.2  --                              C    .040    6.5/4     100:1 106    55,000                                                                             1.0  17.5                            D    .070    11.4/7.02 100:1  22    7,000                                                                              --   --                              E    .024    3.9/2.4   100:1  83    72,000                                                                             0.6  17.7                            F    .017    5.7/3.51  206:1 108   133,000                                                                             --   --                              ______________________________________                                    

COMPARATIVE EXPERIMENT C (a) Catalyst Preparation

Fifty milliliters (0.1 mole) of a 2.0 molar titanium tetrachloridesolution in hexane was added dropwise to 42.2 ml. (0.02 mole) of a 0.593M stirred solution of dibutylmagnesium in heptane at room temperature.The mixture was then stirred 1/2 hour, the solids allowed to settle, andthe supernatant liquid removed by decantation. The solids werereslurried with fresh hexane and the decantation procedure repeated 5more times to remove most of the hexane soluble titanium species. TheMg:Ti ratio was 0.25:1 in the catalyst preparation prior to decantation.

(b) Polymerization of Ethylene

The polymerization procedure of Example (4-b) was repeated using 2.2 ml.of 0.616 M triisobutylaluminum (1.36 millimoles aluminum) and an aliquotof the catalyst slurry prepared in (a) above containing 0.0068millimoles of titanium. Thirty-eight grams of polyethylene was obtainedhaving a bulk density of 11.6 pounds per cubic foot. The catalystefficiency was only 117,000 grams of polyethylene per gram of titanium.

COMPARATIVE EXPERIMENT D (a) Catalyst Preparation

The catalyst preparation procedure of Comparative Experiment C wasrepeated except 18.2 ml. (0.011 mole) of 0.616 M triisobutylaluminum inhexane (11.2 millimoles aluminum) was added to the dibutylmagnesiumsolution before addition of the titanium tetrachloride. The Mg:Ti ratioof the catalyst preparation before decanting was 0.25:1.

(b) Polymerization of Ethylene

The polymerization procedure of Example 4 was repeated using 18.2 ml. of0.616 M triisobutylaluminum (11.2 millimoles aluminum) and an aliquot ofthe catalyst slurry prepared in (a) above containing 0.056 millimoles oftitanium. Polyethylene (114 grams) was obtained having a bulk density of12.9 pounds per cubic foot. The catalyst efficiency was only 42,500grams of polyethylene per gram of titanium.

COMPARATIVE EXPERIMENT E (a) Catalyst Preparation

A n-propyl alcohol solution in hexane (18.8 ml., 0.25 mole, alcohol plus100 ml. hexane) was added dropwise to 422 ml. (0.25 mole) of a stirredsolution of 0.593 molar dibutylmagnesium in heptane. To the resultantslurry was added dropwise a solution of 110 ml. (1 mole) titaniumtetrachloride and 100 ml. hexane. The resultant brown slurry was allowedto settle and the supernatant liquid was removed by decantation. Thebrown solids were reslurried with fresh hexane and the decantationprocedure was repeated 5 more times to remove most of the hexane solubletitanium species. The brown color indicated that thedibutylmagnesium-n-propyl alcohol reaction product substantially reducedtitanium.

(b) Polymerization of Ethylene

The polymerization procedure of Example (1-b) was repeated using 3.3 ml.of 0.616 M triisobutylaluminum (2.0 millimoles aluminum) and an aliquotof catalyst slurry prepared in (a) above containing 0.020 millimole oftitanium. Polyethylene (252 grams) having a bulk density of 18.1 poundsper cubic foot and a melt index of 0.3 was obtained. The catalystefficiency was 263,000 grams of polyethylene per gram of titanium.

EXAMPLE 7 (a) Catalyst Preparation

A solution of 37.6 ml. (0.5 mole) of n-propyl alcohol and 100 ml. hexanewas added dropwise to a stirred solution of 532 ml. (0.25 mole) of 0.470molar dibutylmagnesium in a heptane-cyclohexane mixture diluted with 200ml. of hexane. To the resultant slurry at 40° C. was added dropwise asolution of 110 ml. (1 mole) titanium tetrachloride in 100 ml. hexane.The resultant white slurry was allowed to settle and the supernatantliquid was removed by decantation. The white solids were reslurried withfresh hexane and the decantation procedure was repeated 5 more times toremove most of the hexane soluble titanium species.

(b) Polymerization of Ethylene

The polymerization procedure of Example (1-b) was repeated using 0.80ml. of 0.616 M triisobutylaluminum (0.49 millimole aluminum) and analiquot of catalyst slurry prepared in (a) above containing 0.0050millimoles of titanium. Polyethylene (325 grams) having a bulk densityof 21.9 pounds per cubic foot and a melt index of 0.6 was obtained. Thecatalyst efficiency was 1,360,000 grams of polyethylene per gram oftitanium.

COMPARATIVE EXPERIMENT F (a) Catalyst Preparation

A solution was prepared by mixing 169 ml. (0.1 mole) of 0.593 molardibutylmagnesium in heptane, 32.8 ml. (0.02 mole) of 0.616 Mtriisobutylaluminum in hexane, and 13.5 ml. (0.18 mole) n-propylalcohol. After the alcohol had been slowly added, the solution wasdiluted to 250 ml. with hexane. A 100 ml. aliquot of this solution and150 ml. hexane was continuously stirred at room temperature while 160 ml(0.16 mole) of 1.0 molar titanium tetrachloride in hexane was addeddropwise. The resultant brown slurry was stirred for 1/2 hour, the brownsolid was allowed to settle, and the supernatant liquid was removed bydecantation. The brown solid was reslurried with fresh hexane and thedecantation procedure was repeated 5 more times to remove most of thehexane soluble titanium species. The brown color indicated that thealcohol reaction product with the dibutyl magnesium and ATBsubstantially reduced the TiCl₄.

(b) Polymerization of Ethylene

The polymerization procedure of Example (6-b) was repeated using 2.3 ml.of 0.616 M triisobutylaluminum in hexane (1.42 m moles aluminum) and analiquot of the catalyst slurry prepared in (a) above containing 0.0072millimoles of titanium. Polyethylene (88 grams) was obtained. Thecatalyst efficiency was 255,000 grams of polyethylene per gram oftitanium.

EXAMPLE 8 (a) Catalysts Preparation

A solution (16.0 pounds) of 8.92% dibutylmagnesium in heptane was mixedwith 6.7 pounds of 18% triisobutylaluminum using a jacketed stainlesssteel vessel having a mechanical stirrer. The temperature of thissolution was maintained at about 25° C. while 1,381 ml. of n-propylalcohol was slowly added. A 2.0 molar solution (15.12 pounds) oftitanium tetrachloride in hexane was then added in about 20 minutes. Thewhite solids were allowed to settle and a portion of the supernatantliquid was removed by decantation. The solids were reslurried with freshhexane and the decantation procedure was repeated 10 more times toremove most of the hexane soluble titanium species. The resultant slurrywas diluted with hexane to give a slurry which was 0.30 millimolar intitanium.

(b) Copolymerization of Ethylene and Butene-1

Ethylene and butene-1 were continuously copolymerized in a 150 gallonstirred, jacketed reactor at 85° C. by adding 300 pounds per hourhexane, 50 pounds per hour of ethylene, and enough butene-1 to give thedesired polymer density. Hydrogen was added to the partially liquid fullreactor to maintain about 53% by volume in the gas phase of the reactor.The reactor pressure was maintained at about 170 psig by the rate atwhich the catalyst slurry prepared in (a) above was added. A dilutesolution of triisobutylaluminum in hexane was continuously added to thereactor along with the catalyst at a rate so as to maintain an Al:Tiratio of about 100:1 in the reactor. The polymer slurry was continuouslyremoved from the reactor and the polymer separated from the hexane. Thedried polymer powder had a melt index of 6.7, a bulk density of 25pounds per cubic foot, and a density of 0.957 using method ASTMD1505-63T. The catalyst efficienty was 588,000 pounds of polymer perpound of titanium.

EXAMPLE 9 (a) Catalyst Preparation

Hexane (200 ml.), 167 ml. of 0.750 M dibutylmagnesium (125 millimoles)in heptane, and 57.9 ml. of 1.08 M diethylzinc in hexane were mixed in astirred flask. To the resultant solution was added dropwise a solutionof 28.2 ml. of n-propyl alcohol (375 millimoles) in 200 ml. hexane. Theslurry got hot and some hexane was lost by evaporation. Hexane was addedto give a total volume of about 700 ml. Titanium tetrachloride (27.5ml., 250 millimoles) mixed with hexane (100 ml.) was added dropwise tothe above slurry at room temperature. The solids were allowed to settleand the supernatant solution was removed by decantation. The solid wasreslurried with fresh hexane and the decantation procedure was repeatedfour more times to remove the hexane soluble reaction products.

(b) Polymerization of Ethylene

The procedure of Comparative Experiment (A-b) was repeated using 5.4 ml.of 0.616 M triisobutylaluminum (3.3 millimoles) and an aliquot ofcatalyst slurry from (a) above containing 0.033 millimoles of titanium.Polyethylene (177 grams) was obtained having a melt index of 1.0 and abulk density of 19.1 pounds per cubic foot. The catalyst efficiency was112,000 grams of polyethylene per gram of titanium.

EXAMPLE 10 (a) Catalyst Preparation

Carbon dioxide (30 psig) was added to a stirred solution ofdibutylmagnesium in heptane and triisobutylaluminum having Mg:Al molarratio of 1:2.0. After 2 hours, hexane was added to the reaction mixtureto give a solution which is 0.2 molar in magnesium. A 1.0 M titaniumtetrachloride solution (200 ml.) in hexane was added dropwise to 250 ml.of above 0.2 M magnesium solution. The white solid was allowed tosettle, the supernatant removed by decantaion, and the solids reslurriedwith fresh hexane. This decantation procedure was repeated four moretimes to remove the hexane soluble reaction products.

(b) Polymerization of Ethylene

The procedure of Comparative Experiment (A-b) was repeated using 3.3 ml.of 0.616 M triisobutylaluminum (2.0 millimoles) and a aliquot ofcatalyst slurry from (a) above containing 0.020 millimoles of titanium.Polyethylene (69 grams) was obtained having a melt index of 0.45 and anbulk density of 26.6 pounds per cubic foot. The catalyst efficiency was73,000 grams of polyethylene per gram of titanium.

I claim:
 1. A process for the polymerization of an α-olefin or mixturesthereof under conditions characteristic of Ziegler polymerizationwherein the polymerization is conducted in the presence of(A) asupported catalyst which is the solid, hydrocarbon insoluble reactionproduct formed by reacting in an inert diluent(1) the reaction productof(a) a magnesium component or mixture of such components represented bythe formula MgR₂.xMeR'_(x') wherein each R is independently ahydrocarbyl group having from 1 to about 20 carbon atoms, each R' isindependently a hydrocarbyl or a hydrocarbyloxy group having from 1 toabout 20 carbon atoms, Me is aluminum, zinc or boron, x has a value offrom zero to about 10, and x' has a value equal to the valence of Me;with (b) a sufficient amount of at least one of water, carbon dioxide oran organic, oxygen-containing compound, free of halogen and nitrogenatoms, so as to to react with the hydrocarbyl groups present incomponent (1-a) to produce a product which will not substantially reduceTiCl₄ at a temperature of about 25° C.; with (2) a halide-containingtransition metal compound or mixture of such compounds represented bythe formula TmY_(n) X_(z-n) wherein Tm is a metal selected from groupsIV-B, V-B and VI-B of the Periodic Table of Elements, Y is oxygen orOR", each X is a halogen, each R" is independently a hydrocarbyl grouphaving from 1 to about 20 carbon atoms, z has a value equal to thevalence of said transition metal, n has a value of from zero to 6 withthe value of z-n being from at least 1 up to a value equal to thevalence of the transition metal; said halide-containing transition metalcompound being present in a quantity so as to convert substantially allof the substituent groups attached to a magnesium atom in component (1)to a halide group. (B) an activating agent for said supported catalystwhich activating agent is represented by the formulas AlR³ _(3-m) X_(m),MgR³ ₂, MgR³ X, ZnR³ X or ZnR³ ₂ wherein each R³ is a hydrocarbyl grouphaving from 1 to about 20 carbon atoms, X is a halogen, or ahydrocarbyloxy group having from 1 to about 20 carbon atoms, m has avalue from zero to 2; said activating agent being present in a quantitysufficient to provide an Al, Mg and/or Zn:Tm atomic ratio of from about1:1 to about 5000:1.
 2. The process of claim 1 wherein in component(1-a) each R and R' is independently an aliphatic hydrocarbon grouphaving from 1 to 10 carbon atoms; Me is aluminum and wherein said inertdiluent is a hydrocarbon or mixture of hydrocarbons having from about 5to about 10 carbon atoms and wherein said activating agent isrepresented by the formula AlX_(m) R³ _(3-m) wherein each R³ is ahydrocarbyl group having from 1 to about 10 carbon atoms, m has a valueof zero or 1 and the Al:Tm atomic ratio is from about 5:1 to about1000:1.
 3. The process of claim 2 wherein the value of x and each R andR' is such that the magnesium compound is soluble in said hydrocarbon ormixture of hydrocarbons and wherein each R³ is a aliphatic hydrocarbonand the Al:Tm atomic ratio is from about 10:1 to about 400:1.
 4. Theprocess of claim 3 wherein the value of x and each R and R' is such thatthe reaction product (1) is soluble in said inert diluent.
 5. Theprocess of claim 4 wherein X is chlorine and n has a value of zero andTm is titanium.
 6. The process of claim 5 wherein said magnesiumcomponent is selected from dibutylmagnesium.1/2 triisobutylaluminum,dihexylmagnesium.1/2 triisobutylaluminum, butylethylmagnesium.1/2triisobutylaluminum, butyloxtylmagnesium.1/2 triisobutylaluminum andmixtures thereof and wherein said activating agent is triisobutylaluminum.
 7. The process of claims 1, 2, 3, 4, 5 or 6 wherein component(1-b) is water, carbon dioxide or an organic, oxygen-containing compoundselected from, acetals, ketals orthoesters, carboxylic acid anhydrides,carbonates, glycols or mixtures thereof.
 8. The process of claims 1, 2,3, 4, 5 or 6 wherein the organic, oxygen-containing compound is selectedfrom alcohols, aldehydes, ketones, carboxylic acids, esters ofcarboxylic acids or mixtures thereof and wherein said alcohols,aldehydes and ketones can contain up to about 50% water by weight. 9.The process of claim 8 wherein the organic, oxygen-containing compoundis an alcohol or mixture of alcohols having from 1 to about 20 carbonatoms and which is anhydrous or contains up to about 1% water by weight.10. The process of claim 9 wherein said alcohol is methyl alcohol, ethylalcohol n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butylalcohol, tert-butyl alcohol, phenol, 2,6-disopropylphenol, or mixturesthereof.